Given below are names of techniques (Column X) and their characteristic features measured for molecular characterization (Column Y).

Column X	Column Y
A. X-ray crystallography	i. Fluorescence
B. NMR spectroscopy	ii. Polarization
C. Raman spectroscopy	iii. Diffraction
D. CD spectroscopy	iv. Wave number
E. Colorimetry	v. Chemical shift
	vi. Ellipticity
	vii Absorbance

Which one of the following options represents all correct matches between Column X and Column Y?

Correct option is A

Answer: (a) A–(iii), B–(v), C–(iv), D–(vi), E–(vii)

Explanation

This question connects biophysical and spectroscopic techniques (Column X) with the key measurable features they determine (Column Y).

Let’s go step by step:

A. X-ray crystallography → (iii) Diffraction

X-ray crystallography determines the 3D structure of molecules by analyzing the diffraction pattern produced when X-rays interact with the crystal lattice.
Correct.

B. NMR spectroscopy → (v) Chemical shift

In NMR (Nuclear Magnetic Resonance) spectroscopy, the chemical shift reveals the electronic environment of nuclei (usually ¹H or ¹³C), giving structural information.
Correct.

C. Raman spectroscopy → (iv) Wave number

Raman spectroscopy measures vibrational energy shifts in terms of wave number (cm⁻¹).

Used for identifying molecular bonds and symmetries.
Correct.

D. CD spectroscopy → (vi) Ellipticity

Circular Dichroism (CD) measures the difference in absorbance of left- and right-circularly polarized light, reported as ellipticity (θ).

Used for studying protein secondary structures (α-helix, β-sheet).
Correct.

E. Colorimetry → (vii) Absorbance

Colorimetry measures the absorbance of specific wavelengths of light by a colored solution.

Based on Beer–Lambert’s law.
Correct.